Research on generation of a so-called iPS cell (induced pluriopotent stem cell) and a use of the iPS cell has been actively carried out so as to apply the iPS cell to regenerative medicine, for example (see Patent Literature 1).
The iPS cell is generated by causing a given nuclear reprogramming factor to act on a somatic cell. Therefore, the iPS cell is less likely to cause an ethical problem as compared to an embryonic stem cell (ES cell) established from an early embryo.